Pipe-bending tool



May 7, 1929.- A, B ALLEN 1,712,414

PIPE BENDING TOOL Filed Feb. 5, 1927 I} Illllll INVENTOR A' -Allen,

ATTORNEY5 t May 7, 1929.

UNITED STATES ANDREW B. ALLEN, OF MIAMI, FLORIDA.

PIPEBENDII\TG TOOL Application filed February 5, 1927. Serial No. 166,200.

This invention relates to tools for bending pipes, ,rods and the like, and is more particularly adapted for use in connection with electrical conduits used in electrical wiring.

A primary object of the invention is to so construct a tool of this character that it may be set on any size pipe up to and including three-fourths of an inch conduits at any angle of a curve, elf-set or elbow whereby the bend is to be changed in form, straightened, ofi-set or curved and the tool will become selflocking on the application of leverage no matter whatthe angle may be and will remain inexactly the position in which it is placed until the leverage thereon is manually released and the tool moved into another position.

Another object is to provide a tool of this character so constructed that when used in bending pipes to form elbows, other bends or elf-sets, the tool engages the pipe at points so as to prevent it frgm spreading, flattening, or being disfigured in any manner which will interfere with the free passage of a wire therethrough.

Another object is to so construct the tool that it will not touch that portion of the pipe which forms the inside curve of the bend'and thus avoid mutilation at this point.

Still anotherobject is to provide a nonadjustable, solid, one piece portable pipe bender constructed to form any regulation bend required by the national electrical code with the one tool, thereby eliminating the necessity of-using a separate tool for each size plpe.

Another object of the invention is to construct a tool of this character'with the head or upper jaw advanced to a given measurement from the lower jaw to prevent excess play in bending smaller pipe than threeiourths of an inch, thereby allowing the operator to make a shorter curve or elbow in smaller pipe as may be desired without employing a special size bender tor a special size pipe or resorting to an adjustable tool.

The invention further provides a hand operated tool for bending longitudinal elements embodying coacting oifset jaws provided with teeth or serrations'which successively bite and continuously grip the longitudinal element to gradually bend the same, and positively hold the device against accidental slipping incident to the strain applied to the longitudinal element to bend the latter.

In carrying out these objects, the invention is susceptible of modification without departing from the spirit or sacrificing any of the advantages of the claimed invention; there being shown in the drawings for illustrative purposes a preferred and practical form in which,

Figure 1 represents a front elevation with parts broken out of the tool constituting this invention,

Fig. 2 is a side elevation of the tool taken from the left,

Fig. 3 is a similar view taken from the right,

Fig. 4 is an inside plan view of the upper aw,

Fig. 5 is a similar view of the lower jaw,

And Fig. 6 is a view similar to Fig. 1 and showing a different use of the device.

In the embodiment illustrated the head of the pipe bender is shown provided with an inclined screw threaded stem or attaching stud 2 which is designed to be connected by a standard pipe coupling 3 with the threaded end of a lever 5. If desired the stem or attaching stud may be formed with a socket for the reception of one end of the lever. This connection of the lever 5 with the stem 2 provides for the removal of the lever so that the operator may fasten the tool to a workbench by means of small blocks or in any suitable manner and use the tool for forming elbows, oil-sets, curves, or any shaped bend required in his work, and in which uniform work is required.

The head 10 is formed with a laterally proecting web 7 having a jaw 6 at its upper end.

As particularly illustrated in Figure 1 the jaw 6 is opposed to the head 10. The jaw 6 is provided on its inner face at opposite ends with a plurality of teeth 8 preferably of a size of about one-eighth of an inch by one-eighth of an inch cut on a maximum of one and one-sixteenth inch radius, five full teeth beinghere shown arranged at each end of the jaw 6 and having a smooth rounded portion 9 formed between the teeth, the smooth portion being cut about onethirty-second of an inch deeper than the points of the teeth.

The head 10 is formed with-a downwardly curved extension 11 at one end. This head and extension are formed with a continuous V-shap'ed in cross section groove 14. As illustrated-in Figure 5 the upper face of the extension is formed with teeth 12 while the upperface of the head is formed with teeth 13 at its forward end;

In the use of this tool, the pipe to be bent is inserted through the openin 7 and leverage applied by means of the andle 5,-the pipe being gripped at the'three points indicated in Fig. 3. When the tool is so set and leverage applied thereto, it will remain in exactly the position in which it is placed until the operator releases the leverage and removes the tool to another position, the tool being self-locking when the leverage is applied, no matter at what angle it may be. It will be observed that with my invention the teeth 8 and 12 successively engage the pipe and positively hold the device against slipping to gradually bend the pipe. That is to say, as the bend is being formed the teeth 8 and 12 successively bight the pipe and thereby maintain a positive grip during the entire bending operation. By providing the recess 9, shorter bends in a pipe may be made without mutilating the engaged extremity of the latter. In this connection the inner end of the pipe which is usually threaded'carries a temporary protective element such as a sleeve or bushing which is accommodated in the recess as shown in Figure 6. It will therefore be seen that the pressure of the jaw 6 will be directly on the sleeve or protective element. 4

By constructing the tool with the advanced head and the obliquelydisposed handle or lever, the operator is enabled to make elbows and right angular bends while standing in a normal upright position, thereby avoiding stooping and back-bending in the performance of this work. It will be observed that the extension 11 presents a straight toothed bending surface beyond the axis of the stud on one side thereof and from this point the extension has a curved bending surface. Also the jaw 6 presents a straight toothed bending surface which is located at the opposite side of theaxis of the stud. Thus when manual strain is initially exerted on the pipe or other longitudinal element to be bent the straight toothed bending surfaces will start the vbend. Furthermore these straight toothed bending surfaces positively grip the pipe to positively lock the tool thereon and thereby avoid slipping of the tool and consequential injury to the user.

Without further description, it is thought that the features and advantages of the invention will be readily apparent tothose skilled in the art, and it will, of course be understood that changes in form, proportion, and minor details of construction may be resorted to without departing from the spirit of the invention or its scope as claimed.

I claim 1. In a bending tool, a head having an attaching stud and a substantial extension at one end beyond the axis to said stud presenting a straight toothed bending surface beyond said axis on one side thereof and bcyond that, curved, to engage and exert strain against one side of a longitudinal element, a

web formed with the head and extending laterally therefrom on the other side of the stud from said extension, a jaw formed with the web and projecting at right angles therefrom in opposed relation to the head and presenting a like straight toothed bending surface and adapted to engage the opposite side of the longitudinal element, and a lever rigid with the attaching stud whereby rocking of the lever will exert manual strain on the longitudinal element to bend the same.

2. In a bending tool, a head having an attaching stud and a substantial extension at one end beyond the axis of said stud presenting a straight toothed bending surface beyond said axis on one side thereof'and be yond that, curved, to engage and exert strain against one side of a longitudinal element, the extension having a V-shaped groove, a web formed with the head and extending laterally therefrom on the other side of the stem axis from said extension, a jaw formed with the web and projecting at right angles therefrom in opposed relation to the head and presenting a like straight toothed bending surface adapted to engage the opposite side of the longitudinal element.

3. In a bending tool, a head formed with a curved extension at one end to engage and exert strain against one side of a longitudinal element, a web formed with the head at a point remote from the extension, a jaw formed with the extension and projecting at right angles thereto in opposed relation to the head and adapted to engage the opposite side of the longitudinal element, and a lever rigid with the head whereby to rock the lever to exert manual strain on the longitudinal element to bend the same, the inner face of the jaw having a recess intermediate its ends to accommodate a protective element carried by the threaded end of a pipe to obviate mutilation of the threads thereof incident to the bending operation.

ANDREW B. ALLEN. 

